Re: [9fans] dossrv panics

["Russ Cox" <rsc@plan9.bell-labs.com>]

In dossubs.c:/^getfat, change

	/*
	 * this is a very strange check for out of range
	 */
>>>	if(k >= (1 << fb) - 7)
		return -1;

to

	/*
	 * This is a very strange check for out of range.
	 * As a concrete example, for a 16-bit FAT,
	 * FFF8 through FFFF all signify ``end of cluster chain.''
	 * This generalizes to other-sized FATs.
	 */
	if(k >= (1 << fb) - 8)

(Note the s/7/8/ in addition to the big comment.)
and let me know whether that solves your problem.

On a related note, in dossubs.c:/^truncfile, I think that

	while(clust > 0){
		next = getfat(xf, clust);
		if(n <= 0)
			putfat(xf, clust, 0);
		else
>>>			n -= bp->sectsize;
		clust = next;
	}

should be

	n -= bp->clustsize*bp->sectsize;

It doesn't matter, since we only call truncfile
with a count of 0.

Russ